Application of a three-dimensional virtual model to study the effect of fluoroscopic angle on infra-acetabular corridor parameters and screw insertion rates

Table 2 Measurement results for the ideal position of an infra-acetabular screw under different fluoroscopic angles

	IAD (mm)	IAL (mm)	AIP (°)	IR (%)
5°
Overall	3.89 ± 1.81	80.07 ± 5.79	5.58 ± 5.52	55.61
Male	4.42 ± 1.80	80.76 ± 5.64	3.40 ± 4.21	68.62
Female	3.35 ± 1.66	75.87 ± 6.04	9.15 ± 5.57	42.47
t value	5.96	4.98	− 5.62	χ² = 25.89
P value	< 0.001	< 0.001	< 0.001	< 0.001
15°
Overall	4.08 ± 1.84	85.31 ± 7.25	4.61 ± 5.66	60.42
Male	4.60 ± 1.82	87.63 ± 7.15	2.16 ± 4.33	73.94
Female	3.55 ± 1.69	81.94 ± 6.03	8.61 ± 5.30	46.77
t value	5.82	5.2	− 9.13	χ² = 28.85
P value	< 0.001	< 0.001	< 0.001	< 0.001
25°
Overall	4.08 ± 1.84	92.06 ± 6.95	3.97 ± 5.73	60.42
Male	4.62 ± 1.84	95.02 ± 6.10	1.79 ± 4.31	73.94
Female	3.54 ± 1.68	87.47 ± 5.58	7.57 ± 6.00	46.77
t value	6.06	7.15	− 6.38	χ² = 28.85
P value	< 0.001	< 0.001	< 0.001	< 0.001
35°
Overall	3.99 ± 1.80	95.64 ± 6.70	1.63 ± 5.76	58.56
Male	4.66 ± 1.82	99.49 ± 5.14	− 0.45 ± 4.56	73.4
Female	3.32 ± 1.50	89.80 ± 4.02	5.14 ± 5.90	43.55
t value	7.84	11.91	− 4.4	χ² = 34.34
P value	< 0.001	< 0.001	< 0.001	< 0.001
45°
Overall	3.04 ± 2.18	98.63 ± 7.64	− 0.66 ± 4.87	43.58
Male	4.03 ± 2.02	101.96 ± 5.99	− 1.95 ± 3.88	64.89
Female	2.03 ± 1.85	90.10 ± 3.78	3.13 ± 5.54	22.04
t value	10.27	5.87	− 4.3	χ² = 69.82
P value	< 0.001	< 0.001	< 0.001	< 0.001

IAD, diameter of IAC; IAL, length of IAC; AIP, angle between the IAC axis and the sagittal midline plane; if IAC directed to lateral, a value of AIP was positive. IR, insertion rate; χ², chi-squared

ISSN: 1749-799X